This invention relates to the field of display of multidimensional space, specifically apparatus for controlling the display of selected portions of a multidimensional space to a user and adapted for use with computer systems in virtual reality environments.
Computer visualization and interaction systems such as that described by Maples in "Muse, A functionality-based Human-Computer Interface," Journal of Virtual Reality, Vol. 1, Winter, allow humans to interact with multidimensional information represented in a multidimensional space. Such information can represent many types of virtual reality environments, including the results of scientific simulations, engineering analysis, what-if scenarios, financial modeling, three dimensional structure or process design, stimulus/response systems, and entertainment.
In many of the applications, the multidimensional space contains too much information for the user to view or assimilate at once. Displaying different aspects of the multidimensional space can also aid human understanding. Consequently, the user must select portions of the space for viewing, usually by changing the position and orientation of the human's viewpoint into the multidimensional space. The human must navigate to different what-if scenarios, to visualize different parts of a simulation or model result, to visit different parts of a structure or process design, and to experience different stimulus/response situations or different entertainment features. While the ubiquitous mouse has all but conquered navigation in two-dimensional spaces, navigation in higher dimensions is still problematic.
The mouse and joysticks have seen use as multidimensional display controllers. They are inherently two-dimensional devices, however, and are not intuitive to use when adapted for use in more dimensions.
A three-dimensional spaceball has also seen use as a multidimensional display controller. A spaceball remains stationary while the user pushes, pulls, or twists it. The spaceball does not provide intuitive control of motion because the spaceball itself cannot move. A spaceball can control relative motion, but is ill-suited for large displacement or absolute motion. Booms and head mounted displays combine visualization display with multidimensional display control and can be intuitive to use in multidimensional applications. Booms and head mounted displays can be expensive, however, and the physical limits of the boom structure can limit intuitive navigation. For example, booms typically require an additional input device to control velocity. Booms can control relative motion, but are ill-suited for large displacement or absolute motion.
Other motion devices such as treadmills and stationary bicycles have seen use in multidimensional display control. These are often expensive and too bulky for desktop use. They are also intrusive, often requiring the user to be strapped in to the device. Changing directions in the dimensions using a treadmill or bicycle can also be non-intuitive.
Multi-dimensional tracked objects have also seen use as multidimensional display controllers. These can be intuitive since they can move in multiple dimensions, but they do not allow nonvisual feedback to the user. Tracking can also be difficult when, for example, an electromagnetically tracked device is used near large metal items or an acoustically tracked device is used in settings where line of sight is difficult to maintain.
There is an unmet need for multidimensional display controllers that are intuitive to use, suitable for desktop use, and robust enough for use in a wide range of multidimensional display situations.